Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Change in uncertain tax positions	$ (3.0)	$ 1.1	$ 1.8
Cash paid for income taxes, net of refunds	24.1	105.4	99.5
Accrued interest and penalties	$ 0.3	$ 0.3	$ 0.9